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Stress. That pesky six letter word that has an uncanny ability to wreak havoc on our mental and physical health. By now we have established a working definition of what “stress” is, as well as when and how it manifests itself (discussed in detail here)- arising when we believe we don’t have the resources to cope with the situation at hand- either imagined or real (Lazarus, 1999). Throughout my previous posts I have explored this idea of stress from many angles, examining causes, effects and ways to cope. From this survey of the diverse literature on the topic of stress, some general themes and lessons have emerged.

First, when in the appropriate context a stress response is adaptive and advantageous. Evolutionarily, the physiological cascade of responses triggered in the body in response to an appraised threat is effective at preparing the human or animal to fight or flee from potential danger (Sapolsky, 2004). However, we as humans have the unique ability to conjure up stress in our minds. This has allowed us to perceive seemingly safe contexts as stressful (such as the workplace), subsequently triggering stress responses that are evolutionarily maladaptive (as you won’t be fighting with your computer…at least physically). As such, contexts that elicit stress are now expansive and elusive for us humans in modern times, making stress relatively species specific.

For humans, stress can be both physical and psychological in nature. This duality of stress is perfectly illustrated in Post-Traumatic Stress Disorder. PTSD can develop following a physically stressful event, such as threat of injury or death. However, symptoms of the disorder arise from “reexperiencing” this initial trauma, which occur in the mind in the absence of threat (Yehuda & LeDoux, 2007). Sadly, for us lay folk feelings of stress and subsequent physiological response can arise for far more trivial reasons (can you say first world problems…). For example, if merely trying to figure out how to use constantly changing technology doesn’t cause you stress, the potential it provides for social comparison just might (Ayyagari & colleagues, 2011; Frost & Rickwood, 2017). Interestingly, today, we often hold several ranks depending on the context we are in, thus the tendency to feel like we are at the bottom of the hierarchy is increased (Sapolsky, 2004). Although social subordinance is a common stressor experienced by many species alike, the social hierarchies of today’s society are now defined by a multitude of factors beyond who is the biggest, strongest baboon in the pack, to make matters more stressful than they already were in caveman days…

Regardless of whether perceived stress is physical or psychological in nature, it can lead to significant physical damage. Regardless of whether we are running from a hungry lion, or struggling to keep up with a hefty workload, the longer we endure such stress the more destruction occurs within our bodies. When it comes to the physical toll that stress takes on your body, acute stress is good, as it may help you avoid further physical damage (i.e. becoming a lion’s lunch), but prolonged stress is deleterious. Endure acute stress for a few minutes or hours and our bodies can quickly adapt and recover (homeostatic overload avoided!) (Romero & Wingfield, 2016). Chronically encounter such stress for days, months, or years and we increase our risk for a variety of stress related diseases. As previously discussed and commonly recognized, chronic stress significantly increases risk for cardiovascular disease (examined here). To make matters worse, increased glucocorticoid secretion following activation of the HPA axis makes us reach those high fat foods (effects on metabolism and food choice examined here) (Finch & Tomiyama, 2014), further glomming our arteries, leading to a recipe for disaster when we throw high blood pressure into the mix. These pesky glucocorticoids can also kill cells that support immunity and our ability to fight bacteria and infectious invaders- it is no coincidence that colds increase during final exams! (Cohen and colleagues, 2012). This prolonged stress throws our bodies out of balance, leading to wear and tear and poor physical health outcomes (Romero & Wingfield, 2016).

Solution: avoid all stress and life will be good! Unfortunately, it is not that simple and as previously discussed a little stress is necessary for our species survival. Although our risk for experiencing stress is oftentimes out of our control, we can control the way we cope. As Sapolsky (2004) remarks, although we can’t control our parent’s genes or SES, we can change the way we cope with stress both psychologically and physically. For instance, maintaining a positive outlook (and avoiding rumination) in the face of adversity may contribute to psychological resilience, whereas exercise contributes physical resilience from the negative effects of stress. Furthermore, in an ideal world we increase control and predictability of our stressors and have a vast social support network to help during hard times. However, we don’t live in an ideal world (and those tasks will continue to pile in our inboxes). Good news is that we will eventually habituate to repeated stressors over time, and taking action to proactively manage stress (…breath in…breath out…don’t pick up that cookie!) can reduce health risks exacerbated by that wretched stress (Lipshitz et al. 2015). Here’s a fact, 80% of stress management is accomplished with the first 20% of effort- that is, deciding to make a change. Now that I have a diverse understanding of what stress is and what it can do to my emotions and heath- I vow to make that change!

With the endless amounts of information technology provides us these days, it is relatively easy to find a handful of techniques for managing stress. A quick google search revealed that in order to manage stress I should “avoid caffeine and alcohol, exercise, get more sleep, use relaxation techniques, talk to someone, keep a stress diary, take control and manage my time”…to name a few. From our various readings throughout the semester, we are now well-aware of the multitude of negative impacts stress can have on our bodies, both physically and psychologically and know we should probably adopt a strategy or three to manage this stress…but where does one start? Turns out sometimes getting a little help from others (in this case, in the form of mail-delivered research study) is beneficial in progressing from not even considering a change, to thinking about it, to taking action to manage stress. Evers and colleagues (2006) demonstrated that an individualized TTM-tailored intervention delivered via mail was effective in increasing stress management in a large population-based sample. Participants received communications regarding behavioral changes they could make to better manage stress, including regular relaxation, physical activity, talking with others, or taking time for social activities. Practice of these healthy behaviors increased during and following the guided intervention, along with a decline in practice of unhealthy behaviors and overall levels of stress. Importantly, as Sapolsky (2004) notes, 80% of stress management is accomplished with the first 20% of effort- that is, deciding to make a change. Thus, these types of individualized interventions might provide people with that initial awareness and motivation needed to prompt a change within themselves.

One of the behaviors targeted in Evers and colleagues (2017) stress management intervention was physical activity. Exercise is effective at countering the negative effects of stress for a variety of reasons- it decreases risk for metabolic and cardiovascular diseases, which are worsened by stress (Sapolsky, 2004). Exercise also improves mood. Though colloquial wisdom point to a relationship between regular exercise and stress reduction, how, and if, it reduces reactivity to real life stressors remains unclear in the scientific literature. Using ambulatory assessment Von Haaren (2015) and colleagues attempted to measure the influence of a 20-week exercise intervention in stress reactivity during a relevant real-life stressor in sedentary college students. Results revealed that those who completed the exercise intervention had lower levels of negative affect under conditions of high perceived stress, indicating a reduced level of stress reactivity during final exams. Over time, enhanced stress reactivity, or negative affect, can lead to increased risk for physical and psychological disorders (Sapolsky, 2004). Regular exercise may help to reduce negative emotional reactivity to daily stressors, reducing such health risks. Yet, I also wonder how exercise influences not only stress reactivity, but stress recovery. Does this lower accumulation of negative affect in response to a stressor also influence our physiological and psychological recovery following said stressor? And how might this influence our preparedness to deal with a subsequent stressor?- questions I hope to address in future research!

Another beneficial strategy for stress reduction that has gained significant attention more recently is mindfulness. Last week we examined the degree to which mindfulness mediated the relationship between PTSD symptoms and severity of substance use. Interestingly, Mindfulness Based Cognitive Therapy (MBCT) and Mindfulness Based Stress Reduction (MBSR) have been shown to elicit positive effects on a wide variety of physical and psychological conditions, such as depression and anxiety, as well as fibromyalgia and arthritis. However, the mechanisms behind these positive improvements remain relatively unknown. Alsubaie and colleagues (2017) sought to understand the mechanisms of action through which these mindfulness interventions bring about change, in addition to exploring whether there are universal and/or specific mechanisms of mindfulness interventions that apply to populations suffering from physical and/or psychological disorders. To do this, they employed a systematic review utilizing strict criteria from Kazdin for identifying mechanisms and/or mediators of action. Results indicated that effects of mindfulness interventions (MBCT and MBSR) are mediated through mechanisms of enhanced mindfulness or reduced rumination. However, lack of consistency in theoretical framework, lack of examination of mechanisms involved in physical conditions and reliance on self-report measures yielded equivocal conclusions regarding mechanisms of action for these interventions. Although, the studies included in the review demonstrated the potential for positive outcomes, further research is needed to determine exactly how or why. As scientists we are trained to adopt a skeptical approach to critically evaluate the “how” and “why” of observed relationships. When it comes to stress reduction, if the method through which change is occurring is not harmful or dangerous to the individual then some might wonder- who cares how it works? However, understanding the process that is responsible for change will help us to better understand how these conditions that we are trying to treat arise in the first place. Thus, although we don’t quite understand how MBST and MBSR elicit change, it is important that research examines these questions as it will foster more potent and effective interventions in the future.

Graduate school and stress might as well be synonymous. As grad students we all experience daily, weekly, monthly stress, however, we likely all differ in how we manage this stress. I would like to say that I adopt healthy behaviors during stressful times, but, most of the time this is not the case. I know maintaining a healthy diet and getting daily exercise will make me feel better during particularly stressful times, but sometimes I just cannot seem to follow my own advice. As we learned in previous readings, increases in glucocorticoid secretion following activation of the HPA axis can affect our food preferences, making those cravings for comfort foods all too real. Whereas, sometimes a drink is exactly what I need to take the edge off. Turns out I am not alone when it comes to engaging in such unhealthy behaviors as poor diet, physical inactivity, alcohol and tobacco use (well, minus the smoking for me) to manage psychological stress. Interestingly, these health risk behaviors have been associated with poor stress management. Lipschitz and colleagues (2015) demonstrated that if individuals improved their stress management skills (over a 6-month intervention) this resulted in a composite reduction in health risk behaviors. These results were interesting because they suggested that learning to manage stress in more effective ways resulted in coaction and reduction in multiple health risk behaviors. Thus, acting to make a health change in one domain may be advantageous in prompting change in subsequent behaviors. I have noticed this to be true, finding it easier to maintain a healthy diet when I am also exercising regularly. However, to adopt effective behavior change we must learn to deal with our stress. I have experienced this to be true, finding that I am not only better able to manage daily stress after completing a 4-week mindfulness course last month, but am also better able stay on track with maintaining a healthy lifestyle.

Mindfulness has helped me to better cope with stress and recent research has found similar patterns across a wide variety stress-related disorders, such as PTSD. Not only could greater mindfulness be associated with positive PTSD outcomes, but it might also play in a role in fostering more adaptive coping in individuals with comorbid PTSD and substance use disorders. Bowen and colleagues (2017) were interested in assessing the degree to which mindfulness mediated the relationship between PTSD symptoms and severity of substance use. They found that higher levels of mindfulness, specifically acting with awareness and a nonjudgmental attitude, were associated with lower levels of PTSD symptoms and less severe substance dependence. Thus, training individuals with PTSD to approach their symptoms in a curious and nonjudgmental way might increase their allowance and understanding of their affective discomfort. In turn, by adopting this approach-based relationship with managing their symptoms, this could reduce avoidant-based strategies to managing symptoms, such as substance use.

Mindfulness based stress reduction is a promising avenue for reducing symptoms for a wide variety of stressors, however, we cannot disregard the importance of environmental factors and individual differences. As Sapolsky (2004) detailed, stress increases the reinforcing potential of a drug, thus, those struggling with stress-induced substance abuse find it exceptionally difficult to adopt behavioral changes. Therefore, mindful practice and attention to the sensations of one’s body might be particularly difficult in early stages of fighting addiction. This is especially true when we throw stress into the mix. Stress increases glucocorticoids, which significantly deplete dopamine levels, along with increases in anxiety-mediating CRH levels (Sapolsky, 2004). As such, mindfulness or other intervention techniques are likely to vary in effectiveness depending on the individual and their current experiences. Importantly, when examining adolescent substance use we must consider not only the amount of stress experienced, but also environmental factors. Hoffman (2016) demonstrated that the effects of cumulative stress during adolescence on substance use trajectories during adulthood were mediated by peer substance use. Peers might not only encourage negative coping strategies, but might also remind the adolescent of their adversities. As we can see, when it comes to managing stress (in positive and negative ways), there is no one size fits all solution. So, as individuals managing our own daily stress and as scientists devising effective stress-reduction strategies, we must consider a multitude of individual and environmental factors to find the right fit.

As much as I want to think that the world is a good place, unfortunately our geopolitical climate makes this hard to believe. I think as I get older and am more aware of what is happening in the world around me, I have come to accept the saying that “humans are evil”. A terrible feeling of sadness and dread overcomes me as I type that last sentence. However, the unfortunate evil that surrounds us has been brought to my attention recently. Last week I had to complete a mandatory security awareness training for the army. One of the first videos that was presented was an informational tutorial detailing the steps and processes one should take if you encountered an active shooter scenario. My initial naïve reaction was to wonder why they were presenting this video? When would I possibly need to use these strategies? These initial thoughts of denial lasted for about 30 seconds until I unfortunately remembered the most recent event in Las Vegas, realizing that this is a real scenario that Americans might face. Although I have been fortunate enough to avoid any such tragedies firsthand, I can recall a number of significant events that have occurred in my lifetime. The most significant was the 9/11 attacks. Although it is a terrible memory that scars me, I find it fascinating how vivid that day still feels. I was in the 4th grade in Ms. Kelly’s class. We were doing a reading activity with partners when one of the teachers from down the hall came in and whispered something to Ms. Kelly, whose face immediately dropped, with an expression of sheer terror and fear. Immediately the class was ushered into the classroom next door where we watched as the second plane hit the Towers. The moments after were somewhat of a blur. I remember feeling confused as I wasn’t sure what was happening, but knowing that something was severely wrong as I surveyed the expressions of the teachers faces around me. I remember Ms. Kelly trying to console a fellow teacher, whose father worked in the towers. I then remember being at home with my mom watching the replay of the attacks on the news. Although I was not personally injured or negatively affected by the attacks, it was still a significant event in my life as it had a great impact on many people around me, both near and far. Proximity to such a tragedy is correlated with negative outcomes, but interestingly, it is not always associated with a dose-response relationship in terms of physical and mental symptoms (Garfin & Holman, 2016). Furthermore, though seeking social support through social contact is an effective and adaptive coping strategy following such an event, following the 9/11 attacks the number of daily social interactions did not increase (Garfin & Holman, 2016). This suggests that perhaps there may be some specificity in the use of social support following such acts of terrorism. Additionally, Strand and colleagues (2016) reported how public health of citizens was impacted following a similar act of terrorism in Norway. One of the most striking observations was an 165% increase in suicide rate in the days immediately following the act of terror, in addition to hospitalizations due to schizophrenia, psychosis, myocardial infarction or preterm birth. These findings highlight that acts of terrorism significantly impact physical and mental health, regardless of whether one is specifically involved in the act or not.

Experiencing or witnessing acts of terrorism can have significant impacts on health and well-being, but interestingly, outcomes of presidential elections can similarly elicit feelings of stress. Segments of the American population differentially responded to outcomes surrounding the 2008 and 2016 elections. Our country’s first African American president was elected in 2008, which differentially influenced physiological reactions in citizens. Prior to the election, republicans exhibited stunted cortisol reactions, but following the election social dominance orientation significantly influenced stress responses. Those high in SDO, who endorse a hierarchical arrangement of racial groups, had greater stress response (as evidenced in higher morning cortisol levels) (Trawalter et al., 2011). Perhaps for these individuals, the election of an African American shattered the stability of their endorsed hierarchies, yielding increased feelings of stress. In contrast, the most recent election elicited significant feelings of stress in 52% of Americans. However, stress elicited from the latest election was likely not due to fear that long-established racial or social hierarchies would be abolished, but rather that such hierarchies might come to exist again. Majumder and colleagues (2017) found those who were at risk for election related stress both pre and post 2016 elections were women and those with low household income. Thus, unfortunately this past election brought feelings of stress and anxiety to individuals in groups that have notoriously been neglected in decades past. These literature’s demonstrate that not only do extreme acts of violence or terror elicit a significant impact on us, but changes in those appointed to protect us from such terror also influences our emotional well-being.

We live in a world where we are constantly connected and plugged in. I can instantly engage with friends, family and strangers around the country and around the world at the touch of a few buttons. Although this has undoubtedly made connecting and staying in touch with others more efficient, more research is starting to examine the possible negative outcomes from social network site use. It is likely not a surprise to most of us that social network use, specifically Facebook use, has been associated with have a negative impact on an individual’s mental health and wellbeing. Ability to peer into other’s lives can likely cause one to judge our own lives in comparison. Thus, feelings of psychological distress can arise if we perceive others live (or as they are portrayed on Facebook, SnapChat or Instagram) to be happier or better than our own. These comparisons can be made across many facets of life. For example, comparing our bodies against others can lead to body dissatisfaction and drive for thinness, or potentially judging our financial status against others can lead to feelings of inequity and feeling poor, which can also elicit stress. Previous research has examined the broad associations between SNS use and mental health, however, work by Frost and Rickwood (2017) sought to determine specific mental health outcomes associated with site use. They found that Facebook use was associated with alcohol use, disordered eating and negative body image, as well as feelings of anxiety and depression. They also found greater use was associated with Facebook addiction, wherein individuals engage habitually and compulsively with the site, much like behavioral patterns of other types of addiction. Interestingly, there was a link between passive use and negative outcomes. Passively engaging in social comparison and appearance comparison could lead to brooding and rumination, without facilitating social support to mitigate these negative feelings. Therefore, those who are passively viewing Facebook may not be facilitating and maintaining social connections, which could be a positive outcome of site use. In light of our cultures current climate of constant contact via social media, people have started note the negative effects that such activities could have. Thus, many people have started to go on social media-cleanses, making an effort to unplug and live in the moment. It will be interesting to see whether this type of self-help detox is effective at mitigating certain negative consequences of use and who could benefit from such strategies. Additionally, although constant engagement may have a negative impact on our mental health, ecological momentary assessment has been made possible due to technology. Kirchner and Shiffman (2016) explain that by using mobile communication we can revolutionize research on mental health by easily and unobtrusively capturing individual’s experiences moment-to-moment and linking these to objective measures. Furthermore, we can also capture geographic information, which can provide interesting and important information linking locations and stress-related behaviors or diseases. For example, using GEMA we can assess the effects of air pollution on mood and stress levels. As we can see, technology and social connection has benefits and costs to our mental health. Yet, with the new possibilities to study stress across a variety of ecologically valid situations, we can hopefully use this technology to more effectively target treatments to improve mental well-being.

Technology allows us to streamline our lives, and quickly and efficiently accomplish many of our daily tasks. However, sometimes this can backfire and technology can actually lead to technostress. As Ayyagari and colleagues (2011) describe, this is a modern disease caused by one’s inability to cope or deal with information and communication technologies (ICT’s). They explain how specific characteristics of technology (such as usability, intrusiveness and pace of change) can lead to misfits between and individual’s abilities and demands, as well as their supplies and values. These misfits correspond to stressors that are induced by ICT’s, such as work overload, work-home conflict, or role ambiguity. Interestingly the two strongest ICT-induced work stressors were work overload and role ambiguity. They explained how individuals have a hard time focusing their attention with the constant interruptions and conflicting demands created due to ICT’s. We have undoubtedly all experienced counterproductivity due to technology, which you would think would aid in fostering productivity. Alas, we all fall victim to setting aside writing when that email from a colleague or student pops up and we end up spending 30 minutes engaging, abolishing our previous focus on the writing task at hand. Additionally, ICT can elicit a feelings of work overload, where the work demands exceed and individual’s abilities. As students in the hierarchical academic system, we all struggle with biting off more than we can chew. It is so easy for an advisor or colleague to shoot us a quick email to ask for a favor and we fall victim to thinking that technologies aimed at making our lives easier, such as programs to create experiments or stimuli, end up taking up much much more of our time to navigate and troubleshoot than anticipated. Thus, we are in the constant struggle of constantly being plugged in because we feel as if we need to be, when ultimately it could be hindering our productivity and performance. We would likely all benefit from a computer/email free evening or weekend, however, as Ayyagari and colleagues demonstrated there is a blurred line between work and life which leads to feelings of strain. Since it is so easy to stay connected, I think it is extremely important to set boundaries for ourselves. It is easier said than done and I am constantly struggling with it, but logging off email after 8:00 pm and telling colleagues you will not response to emails on the weekends will likely (hopefully) make use happier and healthier in the end.

Feeling subordinate can be psychologically stressful, but how does the view from the bottom affect our health and well-being? As Sapolsky (2004) explains, studying the influence of dominance hierarchies on stress responding and health in the wild has helped us understand how rank and/or status influences us humans. In non-human primates, low rank can lead to higher resting glucocorticoid levels, as everyday basal circumstances are increasingly stressful. In addition this lower glucocorticoid response when faced with a stressor, ultimately leads to maladaptive and delayed recovery. However, social subordinance does not always lead to chronic stress and increased risk of stress-related disease. In certain species, as well as in humans, sometimes it is actually beneficial to not fill the dominant rank. Additionally, changing stability of these hierarchical rankings can also contribute to stress, or lack thereof, due to reduced feelings of control and predictability (you aren’t sure where who you answer to and who answers to you). Thus, in both humans and other species, chronic stress is not simply elicited due to being at the bottom of the totem pole, more factors are at play. For example, the instance of stress-related disease is dependent upon the type of society an animal lives in, their personal experiences in that society, coping skills, personality (or ability to stay positive in the face of adversity) and availability of social support. This tells us a lot about the importance of the animal-environment interaction. As we previously discussed here, person-environment interactions are important in our appraisals of stress, and thus may play also an important mediating role in how rank in society contributes to health risks.

One way to examine “rank” in humans is through socioeconomic status. Poverty and low SES are consistently related to increased risk of stress-related disease, but like animal models, this relationship is nuanced and filled with moderators. For instance, if you live in an environment with high income inequality, low social cohesion and social capital and a high rate of crime this will increasingly predict poor disease outcome, more so than a low-ranking SES alone. Therefore, it is not simply a linear relationship between low rank and increased risk of stress-related disease, but rather, for humans and animals it is dependent upon the rank and how this rank interacts with environmental factors to determine our outcomes.

Another way to define the rank of an individual is whether they belong to a socially advantaged or disadvantaged group. These groups can be defined by factors such as racial identity, sexual orientation, or weight, among others. Those individuals who belong to socially disadvantaged groups have higher risk for health problems, even at higher levels of SES than their socially advantaged counterparts. Race is one such category through which social hierarchy status or disadvantage develops in the United States. However, interestingly, although racial minorities are typically at higher risk for race-related daily (acute) and chronic stressors, interracial interactions can elicit stress in both racial minority and majority groups. This heightened stress can be driven by anxious expectations of social rejection due to previous experiences of discrimination due to race. In a set of experiments, Page-Gould and colleagues (2014) demonstrated that race-based rejection sensitivity accentuated the perceived demands of an interracial interaction and elicited negative responses, such as heightened psychosomatic symptoms, in those individuals with fewer cross-race friendships. The opposite pattern was true for those individuals with a greater number of cross-race friendships, ultimately serving as a protective factor for those who were sensitive to being rejected in some way due on their race. As such, perhaps previous positive experiences in interracial interactions (due to these friendships) can increase and individual’s belief that they have the resources to cope with situational demands of this interaction. Furthermore, gaining a new cross-race friendship (due to study manipulation) had causal effect on individual’s self-efficacy for such interracial interactions and subsequently reduced stress-related symptoms in those individuals with high race-based rejection sensitivity.

Positive experiences with individuals of differing races can reduce feelings of perceived stress that might arise in anticipation of or during such challenging encounters. This type of positive interaction could potentially be beneficial for those individuals who have a fear of appearing prejudice and subsequently elicit an increased stress-response, marked by heightened cortisol levels, during interracial encounters (Trawalter et al. (2012). As Major, Mendes and Dovidio (2013) outline, future research should apply social psychological theories aimed at understanding intergroup interactions when assessing the effects of social hierarchies on health disparities. Taking this type of approach might help us to better understand the various factors at play in terms of how intergroup, interpersonal and intrapersonal processes affect stress-related health outcomes.

Before starting grad school, I worked as a research assistant in an Army research lab. Whenever I would tell friends and family what I did, the immediate question or remark would be, “oh so you study PTSD”. I would constantly have to correct them and say, no, our work focuses more on the front end, before soldiers are deployed trying to develop ways to optimize and predict performance. We attempt to study how humans perform and respond to different stressful situations, but our lab did not specifically study post-traumatic stress disorder. However, the more I learn about the causes and effects of this disorder, I realize that although we may not have studied PTSD directly, our work was targeted at identifying who might be at risk.

PTSD can occur in persons who have experienced fear, helplessness or horror following threat of an injury or death. Symptoms following such trauma are categorized into clusters, including reexperiencing, avoidance and hyperarousal symptoms. Although soldiers are exposed to traumatic events frequently, not all those who are exposed with develop PTSD. As Yehuda & LeDoux (2007) explain, PTSD results from a failure of mechanisms involved in recovery of physiological homeostasis. Therefore, research has attempted to understand underlying mechanisms and/or pre-trauma individual differences that may make one more vulnerable to developing PTSD. One such method to determine relevant risk factors is to study how the body reacts to an acute stress exposure. Using this type of methodology, a current ongoing study our lab is seeking to determine whether individual differences in response to a startling event (such as a loud noise) can predict stress response recovery following an acute psychosocial stressor (trier social stress test). Preliminary results indicate that higher HRV before the startling event might predict greater recovery after an acute stressor. In contrast, previous work has shown that larger HR responses to a startling event in individuals with PTSD might and reduced stress recovery might be due tonically reduced parasympathetic tone. Yehuda and LeDoux (2007) highlight that a similar pattern of reduced physiological response has been demonstrated with cortisol levels. Thus, pre-existing differences in cardiac and neuroendocrine responses may contribute to posttraumatic recovery. Thus, we can see that there are individual differences contributing to who develops PTSD, which additionally may contribute to how subsequent symptoms of one’s PTSD might affect health and well-being.

As Schnurr (2015) notes, the effects that exposure to a trauma could have on physical health is complex. PTSD specifically could mediate the observed relationship between exposure to such traumatic event and poor health via a variety of mechanisms including psychological, biological, behavioral and attentional. They propose that through “allostatic load”, over time the distress induced by PTSD and subsequent repetitive activation/deactivation of physiological stress response systems may lead to disease and poor health outcomes. One such pathway by which PTSD could influence physical health is through a metabolic change, as PTSD is considered to be a marker for weight gain and/or obesity. Kubzansky and colleagues (2013) sought to determine whether women who develop PTSD symptoms are more likely to gain weight and become overweight/obese, seeking to clarify whether PTSD symptoms precede development of obesity, or if the two are comorbid. Results indicated that PTSD symptom onset was associated with altered BMI trajectory and rate, or increased and faster weight gain over time, compared to those who had not experienced a trauma or those whose symptoms and increased weight status co-occurred. Thus, it may be fruitful to develop interventions that effectively reduce PTSD symptoms to not only reduce psychological distress, but also the physical toll that such stress has on the body. A review done by Hall, Hoerster and Yancy Jr. (2015) indicates that potential interventions might be increased physical activity, or dietary change. It seems that habitual exercise may be effective in reducing PTSD symptoms, specifically hyperarousal. However, the effects of dietary content, or the association between PTSD and binge eating disorder seem to be mixed at this time. Since chroic stress can take a lasting toll on our physical health, and health involves physical, mental and social well-being, future research should aim to determine how PTSD influences health and develop effective strategies for reducing such burden.

We have all likely noticed that pesky relationship between stress and immune function. It’s finals week and you have a million things to do, with seemingly no time to do it…and of course when you would ideally like to be operating at your best, you start to notice that soreness in your throat escalating. I was aware of the link between stress and immunosuppression, but Sapolsky (2004) helped me to better understand the processes by which stress can contribute to making us sick. As Sapolsky discussed, the most common way stress influences immunity is through the actions of glucocorticoids. When a stress response is initiated the release of glucocorticoids, such as cortisol, influence cell-mediated immunity. For example, glucocorticoids can actually induce programmed cell death of lymphocytes, which are a family of white blood cells that include natural killer cells and T cells. These cells are important for recognizing and destroying infectious agents, like viruses or bacteria. However, stress makes us more vulnerable to these agent’s due to immunosuppression. So, as humans we have the ability to make ourselves more vulnerable these predatory agents merely by conjuring up stress in our heads, such as the belief that we can’t possibly complete all our final assignments by the semesters end. So, there is no coincidence that oftentimes when I finally arrive at home for the holidays, after weeks of stressing and studying, I usually feel myself coming down with a cold. Interestingly, research by Cohen and colleagues (2012) confirmed this relationship between prolonged stress and susceptibility to developing symptoms of the common cold. Importantly, they found that the effects of cortisol on cold risk were not simply due to elevated levels of cortisol, as previously believed, but rather due to glucocorticoid receptor resistance on target immune cells that are involved in termination of the inflammatory response. As such, those individuals who reported a major stressful life event AND had higher glucocorticoid receptor resistance prior to being exposed to rhinovirus, were the ones who ultimately developed a cold. This idea that it is not simply an inverse relationship between increased levels of stress hormones contributing to immunosuppression is also illustrated in the time course of the stress effect on immune function. Turns out, immune function is initially increased during the first few minutes after the onset of stressor and this enhancement is due to the actions of glucocorticoids. As the stress response continues, glucocorticoids then begin to elicit immunosuppression, with the goal of returning immune function back to baseline levels. However, it is only with chronic stress where immunosuppression persists that we are increasingly susceptible to disease.

This association between stress and disease has prompted researchers to explore the effects of stress on a wide variety of diseases and disorders that may be perpetuated by stress-induced immune dysfunction, such as cancer and depression. However, as Sapolsky (2004) notes, it is quite difficult to establish a causal link between stress and disease risk. The first step in making this link is to determine that the individual has been stressed, which is sometimes easier said than done. As a research assistant, I ran a study attempting to measure stress response recovery following the Trier Social Stress Test. The study was well-designed, with one slight unavoidable flaw…the Tufts undergrads didn’t seem to be very phased by being asked to give a mock job interview, or perform a difficult mental arithmetic task. This is a common difficulty in stress research. You want to study the effects of stress, but sometimes you might not even be effectivity eliciting such stress. However, when it comes to immunity and stress, even though you can rest assured that a devastating life event (i.e. loss of a parent/spouse) is likely to effectively cause stress, this stress still may not be ultimately linked to disease outcome. This lack of relationship between stress and immunity was evident in a recent study done by Shoemaker and colleagues (2016) examining the relationship between perceived psychological stress and breast cancer risk. The prospective study followed participants over 6 years, yet did not find any real significant relationship between psychological stress and increased cancer risk. Though these results surprised me, it really made me appreciate the complexities of how stress does and maybe does not affect our bodies. Furthermore, understanding these complexities of the human immune system has lead researchers to really dive into how stress could directly and indirectly be effecting our psychological health. As Hodes and colleagues (2015) explain in their review, pro and anti-inflammatory immune responses may either contribute to or be caused by depression. As they detail, there are complex interrelationships between the sympathetic nervous system, immune system and central nervous system. Thus, further understanding how inflammation and immune function functionally contribute to depression will lead to important insights that may help us to foster effective treatments for those suffering.

“Stressed is desserts spelled backward”. This palindrome is comical and all too relate-able, but it is certainly no coincidence. In fact, most people find that during periods of stress it’s much harder to stick to a healthy diet, often finding ourselves reaching for those highly palatable, high fat and high sugar foods. Engaging in this “stress eating” can be both mentally stressful, if it deviates from one’s dietary goals, but also physiologically stressful on our bodies if this dietary pattern is maintained for prolonged periods of time. Sapolsky (2004) helped me understand the impact stress has on our metabolism and subsequent eating behavior. When the stress response is initially activated (in response to either a present or imagined stressor), our appetite a suppressed due to decreased activity of the parasympathetic nervous system and increased activity of the sympathetic nervous system. This leads to increased levels of cortisol which reduces insulin and halts energy storage. I often notice this appetite suppression on exceptionally stressful days. I will be sitting, staring at the computer for hours on end, until 2:00 pm rolls around and I suddenly realize I haven’t eaten lunch yet! However, as this initial stress-induced vigilance starts to wear off, I start to think about what I am going to eat next, often craving pizza or potato chips. Turns out there is a reason why I tend to crave these high fat or high sugar foods. As Finch & Tomiyama (2014) discuss, increases in gluccocorticoid secretion following activation of the HPA axis can affect our food preferences. Interestingly, this stress-induced pattern of eating may dampen physiological and psychological responses. As such, a chronic stress response network has been proposed wherein consumption of high-fat and high-sugar foods elicits a negative feedback effect, inhibiting the neuroendocrine activity that produces stress and related negative emotions. Thus, there is physiological basis behind why “comfort foods” may make us feel better during stressful times. However, since certain foods have this capability to counteract stress and improve mood, this can lead to reinforcement of behavior. In this case, eating is both pleasurable and rewarding, leading to activation of neural reward pathways. Furthermore, gluccocorticoids may enhance this memory of the rewarding association between consumption of energy-dense, palatable foods and reduced feelings of stress further promoting such behavior patterns. Consequently, this is one potential pathway by which obesity might be perpetuated- via chronic stress and its subsequent effects on eating behavior.

There is a recurrent cycle wherein stress affects our mood and food intake, and conversely, food intake influences our stress level and mood. As previously discussed, this may be one pathway through which obesity developed. Furthermore, glucocorticoids and insulin can promote visceral fat accumulation. So, if an unhealthy lifestyle or chronic stress is prolonged and leads to weight gain, poor diet and inactivity, one might be at risk for developing adult-onset diabetes. As Sapolsky (2004) explains, type 2 diabetes occurs when your cells fail to respond to insulin. Stress can be particularly problematic for a diabetic or someone on the verge of such insulin resistance. When a stress response is elicited, constant mobilization of glucose and fatty acids can lead to development of plaques and risk for atherosclerosis. In this case, preexisting symptoms of metabolic syndrome can lead to detrimental effects during periods of stress.

To complicate things, past periods of depression and experience of daily stressors can lead to differing set of maladaptive metabolic responses. Work by Kiecolt-Glaser et al. (2015) demonstrated that a greater number of stressors the day prior to testing resulted in reduced energy expenditure over the 6-hour postprandial period, as well as higher fat oxidation, making it more likely to gain weight. Additionally, women with a history of depression who had experienced more stressors the previous day had higher triglyceride responses. This is associated with enhanced cardiovascular risk, which combined with increased cortisol stress responses can promote accumulation in visceral fat. Thus, we can see that there is a directional relationship between stress, mood and eating behavior. As such, promoting weight loss or healthy behaviors without acknowledging and targeting this important role that affect plays likely won’t lead to successful behavior change. As Magnan, Fennell and Brady (2017) discuss, we must include both affective and cognitive variables when trying to model, understand and promote healthy decision making. In doing so, we may better be able to promote more effective strategies for influencing lasting behavior change.

There has been longstanding knowledge that stress can lead to cardiovascular disease. Although this is a known fact, it may not seem truly plausible until it affects someone you know. One night in college, I was up late studying for a test when I got a call from my dad. He informed me that my mom had experienced an aortic aneurism. Thankfully, it was relatively minor, they placed a stint and she was fine! As I learn more about the causes and effects of stress I think about what could have caused this scary event to occur. Although high blood pressure runs in our family, which was likely the major contributor, it was also a stressful period of time in her life. Sapolsky (2004) helped me to understand the significant role that this stress might have played in her cardiovascular event. Continual activation of the stress response can lead to chronically elevated blood pressure, or hypertension. Chronic elevation in blood pressure leads to increased need for muscle to control the flow of blood through your blood vessels. This causes vascular resistance, where the vessels become more rigid and resistant to blood flow. Blood pressure is now even higher, which can lead to damage of blood vessels and potentially lead to an aneurism. Thus, as my mom was under chronic stress, and was already prone to hypertension, the combination of these two could have been fatal…I am very thankful it was not! As I learned, stress can damage the inner lining of blood vessels, but additionally our body’s attempt to repair this damage can also lead to detrimental effects, such as atherosclerosis. Though the plaque buildup in atherosclerosis is mostly from mobilization of fat stores in the body, when in combination with poor diet (high fat/cholesterol) this could exacerbate CVD risk. As such, when these two factors of chronic stress and poor health behaviors are combined the effects synergize and elevate risk for CVD. It seems to be a viscous cycle where when we are under periods of high stress we neglect to take care of our bodies, when doing so could save us from detrimental health outcomes. Thankfully, my mom maintains a healthy diet, so she could check that risk factor off the list.

So what might make you more prone to developing stress induced CVD? Turns out that it may partly be due to your personality and how you approach everyday encounters. In a large prospective study, Newman et al. (2011) found that observed, or displayed acts of hostility were associated with a doubled risk of incident heart disease as compared to no hostility. My mom is not a hostile person, and does not generally exhibit aggressive behavior or anger towards others. As Newman and colleagues (2011) discussed, it could be that the presence of hostility increases CVD risk, regardless of severity. This idea was highlighted in the fact that any observed degree of hostility increased CVD risk, whereas no observed hostility did not and could serve a protective effect. However, as Whooley & Wong (2011) note, although hostility was predictive of CVD, since hostility is also associated with poor health behaviors such as physical inactivity or poor diet we cannot determine true cause and effect. However, regardless of whether hostility on its own causes increased risk of CVD, if it also has potential to increase unhealthy behaviors that too cause increased risk of CVD then this seems bad enough regardless of whether a true cause and effect relationship exists.

I have discussed what factors could have increased my mom’s risk of CVD, but what could have reduced it? My mom is generally a happy person, with high positive emotionality, which has been associated with lower risk for a variety of diseases. Interestingly, recent work from Tuck and colleague (2017) discovered that not only does trait positive affect reduce risk of CVD, but one’s ability to express positive emotions does as well…good thing my mom is an expressive person! I also wonder whether ability to deliberately express positive emotion is related to an individual’s emotion regulation tendencies? Or even whether cued ability to express positive emotion could be a form of emotional regulation as it may promote social interaction and support from others. Although this particular study did not measure one’s positive expressive ability during an acute stressor, could the ability to do so facilitate resilience, which may also contribute to reduced CVD risk? To be determined!